SO I bought these two lowers at a gun show over six months ago. I decided to hop on my Blackberry while at the show and look up some reviews, and most everything I got back was that Superior is G2G. Fastforward six months and I put one together. Out of spec magwell and where you screw in the pistol grip. One slight mod to the pistol grip with a drill…no biggie. But mags (specifically Pmags) are a tight fit. GI mags drop free. Pmags need to be stripped from and somewhat forced in. I was wondering if it was possible to adjust tolerances a little by polishing the inside of the mag well or something. I’ve already decided not to build on the other lower. Anyone got any ideas other than just cutting my losses and removing my lower parts to get them into another, high quality lower?
some people sand down their pmags, but depending how many pmags you plan to use with it, that could take a while. Thats still a lot easier than trying to do something to the magwell. Which pmags do you have, the older pmags have a tighter fit than the newer production RevM ones.
I don’t have any issues with my Superior Arms lowers, but then again I don’t use Pmags. It sounds to me like the Pmags are the issue. :eek:
not when other people have lowers that drop pmags free without any modification
Do PMAGs drop free from Colt lowers? Yes.
Therefore, PMAGs are not the issue.
Superior Arms, God bless 'em, does not see this as an issue. I am told by a gunsmith friend that they maximize their cutting tools life by allowing them to wear down absolutely to the edge of spec., which creates the tight magwell situation.
They are taking no action to correct for this, and if you want PMAGs to drop free from SA lowers, you need to hand pick or specify that someone there hand picks them for you to do just that.
They are from my home state, and I wish them well, but because there are so many other quality options for AR15 lowers, I recommend against buying their stuff until they see the need to improve their product.
for reference, my DPMS and CMMG lowers all drop free, my friends S&W lowers do too
I have a superior arms lower, and the magazine well is also tight on most mags.
I love the screw to adjust trigger pull as it is by far my cleanest trigger out of all my AR’s… breaks like a glass rod and it is a simple bushmaster FCG.
So lets say I want to correct the mag well issue… Should I just visually inspect and file down the high points and send it off to get refinished?
I like the lower and all, but damn if only I had known when they came to the Tulsa gun show.
Better yet… does anyone install and pin 9mm mag blocks (colt style) in lower receivers?
That might be a fun use for this lower.
After sending back 4 of them for being out of spec. I got my money back. And the post about the tooling wearing out is true. Oh, and according to them it is all Mil-Spec. Make sure to see if they are machined parallel.The last one, the top of the lower was machined off about 10 deg. These were sold straight from them at a gun show. Must be their seconds again.
So Superior goes with the maximum spec and PMAG uses the maximum spec. So it is superior’s fault.
Hahn top loader?
Let’s see… It’s called CUSTOMER service, and PMAGs are popular with the CUSTOMER. In fact, they are wildly popular with CUSTOMERS.
So, if you are Superior Arms, do you
a) fix your fucking product, so you can sell more,
b) blame PMAGs
c) blame the CUSTOMER
d) do both b) and c) and sell less product.
Unfortunately, up to this point, Superior Arms does d).
There is not “fault” to place here. There is just shitty CUSTOMER service. Which includes getting ahead of potential CUSTOMER complaints. When Superior Arms is bigger and more popular than MAGPUL, then they can say whose specs gotta work with whose.
i’ve owned three of superior arms m4’s, i’ve never had an issue, with p-mags or the shitty cheap steel ones, all my rifles have been spaced out, the first one i got was five years ago i think, then another one two years and then my last one seven months ago…they are a small manufacturing shop, the owners have always given me excellent customer service, the old guy actually lives close to me and i’m always welcome to stop by if i ever have issues, haven’t had the need to yet :), and a few of my friends have purchased them after being recommended by me, i dont know, maybe they had a batch of shitty lowers, its possible…
No, they have shitty lowers as the tool wears. 
When they mount and calibrate the new tool, it makes a nice generous mag-well dimension. As it wears/goes out of tolerance, the mag-well gets smaller and smaller, just like any machine process where you remove metal from the inside of something.
Your drill bits do the same thing. The more you use them, the smaller the hole you bore in material.
I suppose they could either re-calibrate more often, or use up tools quicker, if they wanted to. But a smith I know interacts with them, and they indicate that they do not see the need at this time to do that.
So if you can hand-pick, or don’t mind returning a lower, or hey, I am also told they are small and friendly, and will actually shove a PMAG into a lower and see if it drops free before they ship it.
It’s really not the end of the world. I know at least one top tier trainer (Pat Rogers) who does not advocate “drop-free” as a magazine change TTP.